1. Field of the Invention
This invention relates to dental applicances and more particularly to an improved hinge used in the formation of a denture prosthesis.
2. Description of the Prior Art
The use of artificial teeth as substitutes for missing natural teeth dates back to many generations. However, in recent times, this field of dentistry has become extremely sophisticated and provides various prosthesis which can substitute for partial groups of missing teeth or entire replacement of all missing teeth. The use of dental applicances for providing such prosthesis has become very complex and costly. Dental bridges are made in many shapes and forms for attachment to various parts of the mouth and tissue areas. The artificial teeth themselves are formed of various substances such as porcelain, plastic, etc.
In providing a partial denture prosthesis, it is necessary to connect the artificial teeth to the existing natural teeth and to retain them in a fixed position on the mouth ridges and tissues. The artifical teeth are usually placed on a plastic support which resembles the natural gums. The support is then fixed onto a metallic base which sits on the ridges of the mouth, such as the back gums. An abutment attachment is then placed onto the natural teeth. Such attachments can be flexible metal bands, clasps, or other means of attachment. It is then necessary to interconnect the abutment attachment to the metallic base holding the artificial teeth. Such interconnection is achieved by means of a hinge. The hinge not only provide a coupling between the abuttment attachment and the base member holding the artificial teeth, but also permits rotational motion of the two hinged parts to permit proper adjustment of the artificial teeth in the mouth.
In adjusting the artificial teeth during its fabrication, the dentist must frequently bend and turn the dental appliance. During such manipulation, however, the hinge becomes loose permiting lateral movement of the hinge. Such lateral movement, although slight, will subsequently produce a disturbance and inconvenience in the mouth of the user.
The mouth is generally extremely sensitive and any slight lateral movement of the artificial teeth provides great discomfort to the user. Even if the dental applicance is constructed without such lateral movement, when placing it in the mouth and providing the final adjustment there can again be introduced lateral movement to the hinge which will again provide discomfort and pain.
It is accordingly an object of the present invention to provide a distal extension hinged stress breaker which avoids the aforementioned problems of prior art devices.
Another object of the present invention is to provide an improved hinge for use in a dental applicance which can be adjusted to prevent lateral movement.
Yet a further object of the present invention is to provide a hinged stress breaker for a dental applicance which interconnects the abutment attachment with the base supporting the artificial teeth and wherein the hinge can provide rotational movement but prevents lateral movement.
A further object of the present invention is to provide a distal extension hinged stress breaker for a dental appliance, which can be easily adjusted both during construction thereof as well as in fitting thereof, to correct any lateral movement that may have been introduced.
Still a further object of the present invention is to provides a hinged stress breaker for a dental applicance which permits easy fitting of the dental appliance into the mouth and brings about an accurate fit giving comfort to the user.
These and other objects, features and advantages of the invention will, in part, be pointed out with particularity, and will, in part, become obvious from the following description of the invention, taken in conjunction with the accompanying drawings which form an integral part thereof.